Create an anonymous class from a hash

anon_class.rb

def data_transfer_object(options)
  Class.new do
    def initialize(options)
      options.each do |key, value|
        instance_variable_set("@#{key}", value)
      end
    end
        
    options.each do |key, value|
      define_method key do
        instance_variable_get "@#{key}"
      end
      define_method "#{key}=" do
        instance_variable_set "@#{key}", value
      end
    end
  end.new(options)
end

d = data_transfer_object :foo => :bar
puts d.foo # outputs "bar"

puts d.class # outputs anonymous class
Message = d.class # the config class is now assigned to "Message"
puts d.class # outputs "Config"

m = Message.new :blah => :baz # should be able to make an instance from Message
puts m.blah # doesn't work. Message members aren't redefined by the 'new' operator
puts m.foo # this works, but foo doesn't have a value
m.foo = :bar # assign :bar to Message#foo
puts m.foo # outputs 'bar'